/*
struct ListNode {
	int val;
	struct ListNode *next;
	ListNode(int x) :
			val(x), next(NULL) {
	}
};*/
class Solution {
public:
    ListNode* FindFirstCommonNode( ListNode* pHead1, ListNode* pHead2) {
		auto cur1 = pHead1, cur2 = pHead2; // 解法二-等量关系
		while(cur1 != cur2)
		{
			cur1 = cur1 != nullptr ? cur1->next : pHead2; // 为空就到另个链表重新走
			cur2 = cur2 != nullptr ? cur2->next : pHead1;
		}
		return cur1;
    }
};